A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
Date: 2016 Jan 9, 02:49 -0800
The normal shutdown procedure on a steam powered destroyer, and probably all ships, includes "Engage jacking gear." This was a small motor that turned the main shaft(s) very slowly all the time that the engines were down. This prevented the long heavy shaft from sagging and taking a set. I'd guess in the excitement of capturing the German code equipment, someone forgot.